This invention relates generally to a sealing device for rolling element bearings and, more particularly, to a sealing device that compensates for dimensional variations of bearing elements within wider tolerances than sealing devices of the prior art.
In rolling element bearing assemblies, rolling elements are provided in an annular space between outer and inner bearing rings, to reduce friction. It is common to provide sealing devices at the axial ends of such bearing assemblies to retain lubricant within the bearing assembly and to exclude foreign matter from the bearing assembly, where it may cause damage to the rolling elements or the bearing races. Typically, such sealing devices are retained against one bearing ring, turning with that bearing ring while being engageable with the other bearing ring to effect a seal.
In some prior art sealing devices of this type, a substantially rigid elastomeric seal element is installed in an annular sealing groove in one bearing ring. The sealing groove may be a V-shaped groove at an axial end of the bearing ring. A continuous periphery of the seal element is compressed radially inwardly, to allow installation of the seal element over a retaining surface. Due to its resiliency, the seal element then expands radially outwardly into the sealing groove to effect a seal with the bearing ring.
The periphery of the seal element of such sealing devices must be precisely matched to the sealing groove. Excessive interference may result in folding, or buckling, of the periphery of the seal element, preventing the desired seal. Similarly, inadequate interference may result in insufficient biasing of the seal element into the sealing groove to effect the desired seal. The cost of maintaining sufficiently close tolerances in manufacturing both the bearing ring and the elastomeric seal element inflates the price of prior art rolling element bearing assemblies of this type.
The foregoing illustrates limitations known to exist in present devices and methods. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.